factor/extra/spider/spider.factor

143 lines
4.1 KiB
Factor

! Copyright (C) 2008 Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors fry html.parser html.parser.analyzer
http.client kernel tools.time sets assocs sequences
concurrency.combinators io threads namespaces math multiline
math.parser inspector urls logging combinators.short-circuit
continuations calendar prettyprint dlists deques locals
present ;
IN: spider
TUPLE: spider base count max-count sleep max-depth initial-links
filters spidered todo nonmatching quiet currently-spidering ;
TUPLE: spider-result url depth headers fetch-time parsed-html
links processing-time timestamp ;
TUPLE: todo-url url depth ;
: <todo-url> ( url depth -- todo-url )
todo-url new
swap >>depth
swap >>url ;
TUPLE: unique-deque assoc deque ;
: <unique-deque> ( -- unique-deque )
H{ } clone <dlist> unique-deque boa ;
: url-exists? ( url unique-deque -- ? )
[ url>> ] [ assoc>> ] bi* key? ;
: push-url ( url depth unique-deque -- )
[ <todo-url> ] dip 2dup url-exists? [
2drop
] [
[ [ [ t ] dip url>> ] [ assoc>> ] bi* set-at ]
[ deque>> push-back ] 2bi
] if ;
: pop-url ( unique-deque -- todo-url ) deque>> pop-front ;
: peek-url ( unique-deque -- todo-url ) deque>> peek-front ;
: <spider> ( base -- spider )
>url
spider new
over >>base
over >>currently-spidering
swap 0 <unique-deque> [ push-url ] keep >>todo
<unique-deque> >>nonmatching
0 >>max-depth
0 >>count
1/0. >>max-count
H{ } clone >>spidered ;
<PRIVATE
: apply-filters ( links spider -- links' )
filters>> [ '[ [ _ 1&& ] filter ] call( seq -- seq' ) ] when* ;
: push-links ( links level unique-deque -- )
'[ _ _ push-url ] each ;
: add-todo ( links level spider -- )
todo>> push-links ;
: add-nonmatching ( links level spider -- )
nonmatching>> push-links ;
: filter-base-links ( spider spider-result -- base-links nonmatching-links )
[ base>> host>> ] [ links>> prune ] bi*
[ host>> = ] with partition ;
: add-spidered ( spider spider-result -- )
[ [ 1+ ] change-count ] dip
2dup [ spidered>> ] [ dup url>> ] bi* rot set-at
[ filter-base-links ] 2keep
depth>> 1+ swap
[ add-nonmatching ]
[ tuck [ apply-filters ] 2dip add-todo ] 2bi ;
: url-absolute? ( url -- ? )
present "http://" head? ;
: normalize-hrefs ( links spider -- links' )
currently-spidering>> present swap
[ dup url-absolute? [ derive-url ] [ url-append-path >url ] if ] with map ;
: print-spidering ( url depth -- )
"depth: " write number>string write
", spidering: " write . yield ;
:: new-spidered-result ( spider url depth -- spider-result )
f url spider spidered>> set-at
[ url http-get ] benchmark :> fetch-time :> html :> headers
[
html parse-html [ ] [ find-all-links spider normalize-hrefs ] bi
] benchmark :> processing-time :> links :> parsed-html
url depth headers fetch-time parsed-html links processing-time
now spider-result boa ;
:: spider-page ( spider url depth -- )
spider quiet>> [ url depth print-spidering ] unless
spider url depth new-spidered-result :> spidered-result
spider quiet>> [ spidered-result describe ] unless
spider spidered-result add-spidered ;
\ spider-page ERROR add-error-logging
: spider-sleep ( spider -- )
sleep>> [ sleep ] when* ;
:: queue-initial-links ( spider -- spider )
spider initial-links>> spider normalize-hrefs 0 spider add-todo spider ;
: spider-page? ( spider -- ? )
{
[ todo>> deque>> deque-empty? not ]
[ [ todo>> peek-url depth>> ] [ max-depth>> ] bi < ]
[ [ count>> ] [ max-count>> ] bi < ]
} 1&& ;
: setup-next-url ( spider -- spider url depth )
dup todo>> peek-url url>> present >>currently-spidering
dup todo>> pop-url [ url>> ] [ depth>> ] bi ;
: spider-next-page ( spider -- )
setup-next-url spider-page ;
PRIVATE>
: run-spider-loop ( spider -- )
dup spider-page? [
[ spider-next-page ] [ spider-sleep ] [ run-spider-loop ] tri
] [
drop
] if ;
: run-spider ( spider -- spider )
"spider" [
queue-initial-links [ run-spider-loop ] keep
] with-logging ;